So8 A NATURALIST IN THE PACIFIC chap. 



forest flora presenting puzzling points to the student of distribution. 

 The existence of Elaeocarpus in New Zealand admits of a simpler 

 explanation than the occurrence of the same genus in ■ Hawaii. 

 Pandanus in Fiji is a more difficult genus from the standpoint of 

 dispersal than Corynocarpus in New Zealand, and in fact, than any 

 of the non-coniferous genera of forest trees in that region. 



Whilst it is likely that birds of the genus Porphyrio have, up 

 to almost recent times, been active in distributing the seeds of New 

 Zealand plants outside the region (see p. 296), it would seem that 

 the fruit-pigeons, as represented by a solitary peculiar species of 

 Carpophaga, have long since ceased to be active in this direction. 

 It is true that Sir W. BuUer gives a long list of trees, including 

 Corynocarpus, Elaeocarpus, Litsea, Olea, Podocarpus, and many 

 others, the fruits of which are appreciated by this pigeon ; but since 

 the bird is confined to this region its efforts in plant-dispersal possess 

 only a local interest. Mr. G. M. Thomson, indeed, has expressed the 

 opinion {Trans, and Proc. N.Z. Instit. vol. 33) that in recent 

 times not a single plant has been added through the agency of 

 birds to the New Zealand flora. Besides the regular migratory 

 birds two cuckoos only reach the region, the one from Australia 

 and the other from Polynesia ; whilst Australian birds which had 

 managed to survive the long flight across the ocean have been met 

 with only at times on the west coast of the North Island. From 

 the standpoint adopted in this work we should have expected that, 

 with the exception of current-dispersed plants, New Zealand would 

 be out of touch with the world outside. Varied only by occasional 

 inrushes of plants, its history, dating back to the Mesozoic age, has 

 been one of insular isolation. 



When, however, we apply the principles of plant-dispersal in the 

 Pacific, deducible from the study of the Hawaiian flora, we learn that 

 the stocking of New Zealand with its plants could have been carried 

 out (with the exception of the Coniferae and a few other genera 

 like Fagus that are in a geological sense ancient denizens in this 

 region) by the agencies that stocked Hawaii with its flora. New 

 Zealand genera like Elaeocarpus, Sideroxylon, Sophora, etc., that 

 are represented in the forests of Hawaii, could not be taken to 

 illustrate any former continental connection. If we, so-to-speak, 

 put the New Zealand forest flora in the Hawaiian sieve, all will 

 pass through with the exception of Fagus, the genera of the 

 Coniferae, and plants of similar history in high southern latitudes. 

 This residuum belongs more to the palaeobotanist than to the 

 student of means of dispersal. 



